Best Acceleration Load for a 2.5L non-turbo Subaru

[kennybobby]

i used this site's online tool to calculate power and fuel consumption for the various runs listed from quickest to slowest:

<table>
time    hp    kw      mL of fuel  meters at cruise
3       58     43     14.26          379
4       44     33     14.42          372
9       19.4  14.5    14.67         337
12     14.5  10.8     14.43         317
17     10.3  7.7      14.36         282

At 50 kmh cruising requires 3.7 hp or 2.8kW and the fuel rate is only ~3.0 L/hkm. There is definitely a trade off between acceleration time and cruise time. The 30 to 60 kW region of the BSFC at high load/WOT is the most fuel efficient and maximizes the time in the low power and fuel usage of cruise mode. The really slow run--well you were only making about 10 hp and you can see on the BSFC that it is not very efficient, plus it incites road rage in the drivers behind you...lol. The 3 second WOT run uses less overall fuel than any of the other runs, which was my point/question earlier in this thread, but all the runs used nearly the same amout of fuel to cover the same distance--hard to really pick a clear winner here...

[serialk11r]

Originally Posted by ever_green

here is todays tests i did with avg fuel consumption at the end of 400m run, load % and acceleration times(0-50kmh)

12lhk at 80%, 12s
11.9lhk at 90%, 9s
11.5lhk at 60%, 17s
15.8lhk at wot 3-4s

once again the miserably slow 60% load gave best consumption number. but it seems 90% engine load is the healthiest BSFC number. i did not monitor engine rpm. b
maybe shifted at 3000rpm first and 2800 second gear.

Thanks for the data! Just curious what are the rpms you're seeing?

[ever_green]

with the automatic lower loads shifts at lower rpms. wot was 5000 rpm, 90% load about 3000rpm and 60% load about 2000rpm. cruising all at 1500rpm or less.

this week i have been shifting at 2000rpm and 70% load and my mileage has improved. seems 80% load and 3000rpm is not what my car likes.

[ever_green]

hey i just learned that the high lift cams switchover is varied dependig on engine load anywhere between 2000-4000rpm to improve torque. its not like the vtec system where its fixed at a specific engine rpm.